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Stefán Ingi

Sigurdarson

CFIceland · Go Ahead Eagles

№ 464454Established €428k +1.54

Player dossierEredivisie

Stefán IngiSigurdarson

CFCentre-ForwardAttack

Club
Go Ahead Eagles
League
Eredivisie
Nationality
Iceland
Age
25
Height
194 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Sigurdarson at €2M. Model A, which never saw Sigurdarson during training, estimates €428k: the market value is 368% above that estimate.

That is a factor of ×4.68. Model A's typical held-out miss is ×1.50 either way, so this gap is larger than its usual error.

Without league and club, Model B estimates €679k, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▲ +1.54A €428k▲ +1.08B €679k
Pitch length is a log value scale fitted to this player's figures. ● observed · ◇ Model A · dashed ◇ Model B · each arc is a residual, log(observed) − log(estimate).
Apps
14
Minutes
637
Goals
3
Assists
0
Started
8/14
Min / app
46
Cards
0Y 0R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Sigurdarson…

SHAP describes the model's arithmetic for this player's inputs, not what causes market value. Model B can be explained only by the live service; Model A also has a published explanation for the research players.

Model A vs Model B against the observed €2M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2MModel A €428k

Asking the prediction API…

Held-out estimates come from cross-validation, with this player outside the training data: the honest comparison. Served models were refitted on every player, this one included, so they sit closer to the market. Shaded band: Model A's typical miss (×1.50 either way).

Player traitspercentiles vs 1,583 attackers

Stefán Ingi Sigurdarson's percentiles among attackers: Goals per 90 80th, Assists per 90 6th, Minutes, two years 7th, Starts 47th, Minutes, last 365 days 21st, European club minutes 28th80thGoals6thAssists7thMinutes47thStarts21stRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.42 this player0.26 attacker median80th percentile

0.00peer deciles · median line · this player ●1.17

No passing, progression or defensive actions exist in the dataset, so no trait claims to measure them.

Valuation history every Transfermarkt valuation on record

First valuation
€25k
Dec 2020
Peak
€2M
Dec 2025
Model target
€2M
May 2026
Valuations
12
4 club changes
May 2026€2MGo Ahead EaglesValuation the model is trained to reproduce

May 2026: €2M, Go Ahead Eagles. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-12-01€25kBreidablik Kópavogur
2021-10-16€25kBoston College Eagles (Boston College)
2022-10-01€100kBoston College Eagles (Boston College)
2023-10-02€300kPatro Eisden Maasmechelen
2023-12-28€400kPatro Eisden Maasmechelen
2024-06-20€350kPatro Eisden Maasmechelen
2024-09-17€450kSandefjord Fotball
2024-12-12€450kSandefjord Fotball
2025-06-18€1MSandefjord Fotball
2025-09-08€1.8MSandefjord Fotball
2025-12-15€2MSandefjord Fotball
2026-05-28€2MGo Ahead Eagles

Audit context group-level, not about this player

Audit group
UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
+1.543

The group comes from first-listed citizenship and is never a model input. Across the population, non-UEFA players' market values sit about 10% above Model A's held-out estimates, relative to UEFA players in the same leagues. One player's residual says nothing about that pattern (typical miss ×1.50), and none of it is evidence of discrimination: the target may itself be biased. Open the Fairness Audit

In context observed value among comparable players in this build

All players in the Terminal →

Eredivisie425 players · median €1M

Valued above 62% of the 425 Eredivisie players.

€75k€500k€3M€20M€2MSee them in the Explorer →

Attackers, all leagues1,583 players · median €2.5M

Valued above 44% of the 1,583 attackers.

€20k€300k€5M€75M€2MSee them in the Explorer →

Where Sigurdarson appears

Watchlists and the comparison tray are kept in this browser only.

Near this valuation closest observed values: same league, then same position

Counts and ranks of observed Transfermarkt values only; model errors are never ranked here. Full player export: Every player in the modelling population (D-011).